X Theme drop down menu auto-opens WordPress

SOLVED

The mobile menu on this site:

adriannestrickland.com

Is automatically open when in a mobile format (you can just reduce the width of your browser to see). I'm sure it's some of the custom CSS that's doing it, but I can't figure it out. I'd love it so that the mobile menu is hidden until the 'reveal' button that is already there is clicked/tapped.